Travel From North to South around Mt.Fuji by bus?

Hi, first time posting here, I need your help please.

I need to get from Kawaguchiko to Osaka, but according to Google Map and Hyperdia, to do that I would have to go back to Tokyo, around to Yokohama and then to Osaka. This would take about 5 hours and I am looking for better options.

Please see the map attached. As circled in red, Kawaguchiko station is at the top, and there is Fuji station at the bottom.

Would there be a possible that there is a bus that takes the 138 or 139 highway that goes directly from top to bottom?

And so I can continue to take train to Osaka from bottom to save some time?

Thanks in advance.

In order to reach the shinkansen (Nozomi, to be precise) Shin-Yokohama is your best bet. Taking local trains via Otsuki-Kofu or Otsuki-Nagoya would cost you much more time, as would any local bus given there's one along R138/139.

Mr. thomas's proposal reaches Osaka earliest.

There is a bus from Kawaguchiko Station to Shin-Fuji Station.
Fujikyu Bus.
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Kawaguchiko Station 9:28 -> Shin-Fuji Station 11:33

Other ,There is a bus which goes to Osaka Station from Kawaguchiko Station.
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